Code:
alias test2 {
  var %d = test | if ($dialog(%d)) { dialog -k %d }
  load
  did -a %d 1 aaa
  did -a %d 1 bbb
}
alias test4 {
  var %d = test | if ($dialog(%d)) { dialog -k %d }
  Load
  did -a %d 1 aaa
  did -a %d 1 bbb
  did -a %d 1 ccc
  did -a %d 1 ddd
}

alias -l load { var %d = test | if (!$dialog(%d)) { dialog -mdv %d %d } | else { dialog -ev %d %d } }
dialog test {
  title "test"
  size -1 -1 229 130
  option dbu
  combo 1, 3 104 53 50, sort size edit hsbar vsbar drop
}

after /test2 the arrow buttons to scroll through the 2 items are very small, with /test4 they are normal for the 4 items